Boiler



April 9,

F. HERTEL BOILER Filed June 4, 1938 4 Sheets-Sheet x I five/7Z0.- I l 96% I 1/ x F. HERTEL April 9, 1940.

BQILER Filed June 4, 1938 4 Shouts-Sheet 2 F. HERTEL BOILER Filed June 4, 1938 4 Sheets-Sheeti F. HERTEL BOILER Filed June 4, 1938 4 Sheets-Sheet 4 Patented Apr. 9, 194p 1 UNITED (STATES rAr-ENT OFFi-CE I f 4 m 12,196,631 I I V BOILER Franz jHe'rtel, Steglitz, Berlin, Germany, assignor of one-half to Karl Franke, Berlin, Germany Application June 4,1938, Serial No. 211,904 I In- Great Britain-lune 19, 1937 This invention relates to boilers, and more particularly to boilers of the-kind which are em-,

ployed" for the collective heating of living rooms and the like, and it hasfor its objects toprovide a structural embodiment of the elements'from which theboiler is builtup; and an assembly of the same, by; means of which there is a" saving of material, whilst at the same time there is obtained an extensive separation into; a com l-o" paratively large numberv of single elements hav g6 furnished .with readily cast semi-circular corruing uniformly thin walls, sothat upon the-occurrence of inner stresses in the material-owing to heating and cooling cracks and like injuries are avoided. "Provision is also made "for the heated-water from each single element to be di's charged'fromtheboiler bytheshoitest route. In. this way a greater lift is impartedftothewater, whereby the complete heating system is rapidly The invention alsoirelates to an embodiment gations. of small radius, by means of which these heating surfaces subjectedtothe maximum. heat.

aredoubled in size. l

It has; already been proposed to constructv a 3'6 boiler from separate elements on the'lines of a.}"

radiator andto dispose the same'in such fashion that they enclose a central space forming :a..fuel. shaft. 'In this connection, however, there has not been sufficient economic utilisation of the '5 furnace gases, which have beenconductedalong,

the walls of the elementsonly inthe one direction.

It also heen tlroposed to produce a boiler frornlrtubular elements, whichare situated in close '11 proximity to one another but are flattenedlatf I certain points or so disposed as, to form'dow'ncomer passages for the furnace gases, andare connected at the topancl' the bottom to collecting pipes. Here again, however, there is an insufii cient economical--utilisation of the heating gases.

The boiler according to the invention. combines I the following features:

The single elements,v which are'in. the forin of V fiattened'tubes of hollowlenti'cular crosssection .and adjoinv each other atth'eir narrow; sides, are

conducting the: water? are interconnected. at the top and the b'ottomby' transverse pipes opening;

directly into-top. and: bottom collecting pipes which extends across the fire shaft and the ash boX in the lengthwise direction of the boiler. The elements which form one or both side walls of the shaft are furnished at the top with gaspassages leading towards the fines which are formed behind the side elements between them and additional elements and ope'n out' into a common draught passage, The grate consists of parts integral with the lower collecting pipe and the transverse pipes opening out into the same or isseparate therefrom but is placed in direct heatconductive connection therewith. there'are ensuredthe advantages according to the invention, viz.,a savingoflmaterial, division of the boiler intoinumerous singleelisments having uniformwalls, so that thereare no accumulations of material at certain points in. which cracks or other damage may readilyoccur, considerable circulating power of the heated Water and cooling of the grate by the Water returned. The elements forming the front and rear walls of the shaft are furnished with passage waysiorfurnace and ash I openings.

An additional important feature of the invention consists in the fact that the Walls of the elements enclosing the shaft'are provided with semicircular" corrugations of comparatively small radius. It has alreadybeen proposed in other boilers to rovide ribs or fins extending into the furnace space, but these, however, have various disadvantages, as, the spaces between the same cannot be seen from the furnace. door and also cannot be cleaned from that point, so that they assist the baking of slag thereonand accordingly readily burn.

The corrugations according to the invention are for this reason in thefor nof semicircles having a small radius, in'orderthatthe surfacelike character of the bounding walls of the shaft shall be maintained despite. the fact that the heating surface is doubled, the corrugations being so small that the baking onof slag can be ob served'from the door of the. shaft and accordingly prevented In the practical embodiment of the grate: composed'of one piece together with the pipesfor the: returning water or provided in heatconductive connection with the samei the arrangement in accordancewith the invention is such'that the grate consists of single parts, ,each' part ineluding a piece or. thecol le'ctin'g pipeand a trans- In this way which-: the gratebars .proj ect at right angles vto-.

wards. both sides: Inthis coimectionv the arrangement may be such that the front half of the first grate portion and preferably also the rear half of the final grate portion are not divided into grate bars, the middle grate portion extending over this section in the form of a flat surface and. thus providing a stoking area.

An embodiment of the invention is illustrated by way of example in the accompanying drawings, in which:

Fig. 1 is a cross-section through the boiler.

line 22 in Fig. 1.

Fig. 3 is a vertical longitudinal section along the line 3-3 in Fig. 1, and

Fig. 4 is a View looking towards the front wall and the bottom with projecting hollow bosses.

The wallsof the elements bounding the fire shaft on all four sides are furnished with corrugations of small radius, as shown in Fig. 2. The single elements disposed transversely one against the other are connected at the top and the bottom to transverse connecting pipes 2 and 3, which open out into the central collecting pipes 4 and 5. These collecting pipes extend, in the front to back direction of the boiler, across the furnace shaft and the ash box below the grate 6, and serve for the discharge of the heated water (through the collecting pipe 4) and the return ofthe water to be re-heated (through the collecting pipe 5). Since each single element is connected in direct fashion through the medium of the transverse pipes 2 and 3 to the'collecting pipes 4 and 5, the water ascending in the single elements by reason of the heating takes the shortest path tothe collection pipe, so that there is considerable lifting and circulating power of the water with rapid heating of theheating units connected with the collectin pipes. As'shown by Figs. 1 and 3, the single elements l which bound the furnace shaft on one side are'furnished at the-top with gas passages l, which are preferably interrupted 1n grid-like fashion (Fig. 3) and open out into flues ill, which are formed between the elements and in turn open out into'a lower collection passage 8 with a damper 9.

In Fig. 1 the furnace shaft is located towards one side of the boiler as it is bounded along one side only by one row of single elements and along the opposite [side wall by three rows of to at single points;

The single elements la forming the front wall of the boiler are furnished, according to Fig. 4 with passage ways for the furnace door and the ash door.

The single elements la and ,lb forming the front and rear walls are connected at the top and the bottom by means of their hollow bosses to the.

disposed parallel to the collecting pipes.

The grate is preferably integral with thelower transverse pipes 3 and the lower collecting pipe 5,

and is sub-divided in accordance with the number of transverse pipes 3, as shown in In each grate section there'is provided a section of the collecting pipe 5 and in each case a transverse pipe 3. Above the transverse pipe 3 there is provided a grate bearer, from which the grate bars 60. extend on both sides. In the front half of the first grate'section and the rear half of the final grate section this separationinto bars is omitted, so that stoking areas are formed. By

reason of this separation of the grate each trans- Fig. 2 is a horizontal section taken along the verse connection of single elements with the grate and the transverse pipes and with the parts of. the collecting pipes 4, and 5 consisting of one piece with the transverse pipes may be performed separately, whereupon these parts are aligned to form the length=of the boiler. This represents a very simple assembly or also disassembly in the event of repairs. It has been found, however, that a boiler according to the invention may be maintained in use for a number of years without damagawhich is due to the fact that accumulations of material, such as in part were inevitable in previous boiler constructions, are avoided. There is the same thickness of wall at all points. If, therefore, expansion occurs asthe result of heat this has a uniform effect throughout.

Instead of producing the grate sections with the a pertaining transverse pipes and the collecting pipe sections in one piece as shown, the grate the grate sections.

What I claim'as'newv and desire to secure .by Letters Patent is:

. l. A boiler. consisting of a plurality of individual elements in the form of flattened tubes of hollow lenticular crosssection disposed to form the front and rear and side walls of a chamber forming a furnace shaft. said elements adjoining one another at their narrow sides, transverse pipes interconnectingthe water conducting interior spaces of said elements at the top and at the bottom thereof, colllecting pipes extending across the furnace shaft at the top and at the bottom and having said first pipes opening thereinto, the elements forming a side wall of the shaft being provided at the top with gas passages leading to fines formed between such side elements and additional elementsand opening into a common discharge passage, and a grate disposed over the lower'oollecting and transverse pipes and having heat conductive connection therewith.

2. A boil-er according to claim 1, in which the I elements forming the. front and rear walls of the shafts are connected by water conduitswith the transverse pipes extending between the side wall elements, the said front wall elements havinga fuel and 'ash openingformed therethrough.

3., A boiler, constructed in accordance with claim 1, in which the walls of the elements enclosing the shaft are formed to have substantially semi-circular corrugations of small radius.

4. A boiler constructed in accordance with claim 1, in which said grate is formed in sections, each of said grate sections including a section of the lower collecting pipe and a transverse connecting pipe, the grate sections having flat tops in a common lane forming a fiat grate area, the front and rear sections having bars exintermediate grate sections having oppositely-directed bars upon two sides thereof, the adjacent bars of the sections being in spaced end toend relation.

5.- A boiler structure of the character described,

comprising a plurality of vertically disposed individual elements in the form offlattened tubes of hollow lenticular cross-section disposed to form the front, rear and side walls of a furnace combustion chamber, the tubes of each of .said walls being in edge to edge adjoining relation, one of said walls being made up of a' series of rows of such tubes in edge to edge relation, the tubes being joined at their upper and lower ends for the top and at the bottom and having said transverse pipes opening thereinto, the tubes forming the said one ofthe walls being provided at thetops with gas passageways leading .into longitudinally extending areas between the rows of the tubes of the said one wall, said areas at the lower end of the boiler communicating with a gas leadofi flue, and a grate disposed in the lower portion of said chamber and having the said lower transverse and collecting pipes formed integrally therewith. r

6. A boiler structure of the character lescribed,

comprising a plurality of vertically disposed individual elements the form of flattened tubes of hollow lenticular cross-section disposed to form the front, rear and sidewalls of a furnace com-1 bustion chamber, the tubes of eachof said walls being'inedge to edge adjoining relation one of said'walls being made up of a series of rows of such tubes in edge to edge relation, the tubes being joined at their upper and lower ends for the passage of water from one to the other thereof, transverse pipes interconnecting the water conducting interior spaces of said tubes at the top and bottom thereof, collecting pi'pes extending ,across the furnace combustion chamber at the top and at the bottom and having said transverse pipes opening thereinto, the tubes forming the said one of the walls being provided at the tops with gas passageways, leading into longitudinally extending areas between the rows of the tubes of the said one wall, said areas at the lower end of the boilerc'ommunicatingwith a gas lead-off flue, and a grate disposed in the lower portion of said chamber and having the said lower transverse and 'collecting'pipes formed integrally therewith, the inner walls of those tubes defining the said combustion chamber being formed to provide longitudinally extending semicircular corrugations.

FRANZHER'I'EL. 30 

